Department of Plastic & Reconstructive Surgery/Mayo Burn Centre, Mayo Hospital, King Edward Medical University, Lahore, Pakistan.
Department of Surgery, Montefiore Medical Center, New York, USA.
BJS Open. 2023 Sep 5;7(5). doi: 10.1093/bjsopen/zrad089.
Conflicting evidence exists regarding the optimal waiting time for stable analgesic and vasoconstrictive effects after local infiltration of lidocaine with epinephrine. An objective review is needed to dispel surgical dogma.
This systematic review (PROSPERO ID: CRD42022362414) included RCTs and prospective cohort studies. Primary outcomes were (1) onset of analgesia and (2) onset of stable hypoperfusion, assessed directly, or measured indirectly using perfusion imaging. Other data extracted include waiting strategies, means of outcome assessment, anaesthetic concentrations, volume/endpoint of infiltration, and injection sites. Methodological quality was evaluated using the Cochrane risk-of-bias tool for randomized trials. Articles describing waiting strategies were critically appraised by the Joanna Briggs Institute tools.
Twenty-four articles were analysed, comprising 1013 participants. Ten investigated analgesia onset. Their pooled mean was 2.1 min (range 0.4-9.0 min). This varied with anatomic site and targeted nerve diameter. Fourteen articles investigated onset of stable hypoperfusion. Four observed bleeding intraoperatively, finding the minimum time to hypoperfusion at 7.0 min in the eyelid skin and 25.0 min in the upper limb. The ten remaining studies used perfusion imaging, reporting a wide range of results (0.0-30.0 min) due to differences in anatomic sites and depth, resolution and artefacts. Studies using near-infrared reflectance spectroscopy and hyperspectral imaging correlated with clinical observations. Thirteen articles discussed waiting strategies, seven relating to large-volume tumescent local infiltration anaesthesia. Different waiting strategies exist for emergency, arthroscopic and cosmetic surgeries, according to the degree of hypoperfusion required. In tumescent liposuction, waiting 10.0-60.0 min is the norm.
Current literature suggests that around 2 min are required for most patients to achieve complete analgesia in all sites and with all anaesthesia concentrations. Waiting around 7 min in eyelids and at least 25 min in other regions results in optimal hypoperfusion. The strategies discussed inform decisions of when and how long to wait.
局部浸润麻醉中，利多卡因加肾上腺素后稳定的镇痛和血管收缩效果所需的最佳等待时间存在相互矛盾的证据。需要进行客观的综述来消除手术中的传统观念。
本系统综述（PROSPERO 注册号：CRD42022362414）纳入了随机对照试验和前瞻性队列研究。主要结局是（1）镇痛起效时间和（2）直接评估或使用灌注成像间接测量的稳定低灌注起效时间。提取的其他数据包括等待策略、结局评估方法、麻醉浓度、浸润的容量/终点以及注射部位。使用 Cochrane 偏倚风险工具评估随机试验的方法学质量。描述等待策略的文章使用 Joanna Briggs 研究所工具进行批判性评价。
分析了 24 篇文章，包括 1013 名参与者。10 篇文章研究了镇痛起效时间，其汇总平均值为 2.1 分钟（范围 0.4-9.0 分钟）。这与解剖部位和目标神经直径有关。14 篇文章研究了稳定低灌注的起效时间。4 篇文章在术中观察到出血，发现眼睑皮肤的低灌注时间最短为 7.0 分钟，上肢为 25.0 分钟。其余 10 项研究使用灌注成像，由于解剖部位和深度、分辨率和伪影的不同，报告了广泛的结果（0.0-30.0 分钟）。使用近红外反射光谱和高光谱成像的研究与临床观察相关。13 篇文章讨论了等待策略，其中 7 篇涉及大容量肿胀局部浸润麻醉。根据所需的低灌注程度，急诊、关节镜和美容手术有不同的等待策略。在肿胀脂肪抽吸术中，等待 10.0-60.0 分钟是常规做法。
目前的文献表明，大多数患者在所有部位和所有麻醉浓度下达到完全镇痛需要大约 2 分钟。在眼睑等待约 7 分钟，在其他部位至少等待 25 分钟，可达到最佳的低灌注。所讨论的策略为何时以及等待多长时间提供了信息。
